of New Spain, near Moran. It was only found by Humboldt on the mountain Cerro de las Nahajas, at an elevation of 4800 ft. (800 toises). It is on this mountain that the stones (obsidians) are found, in great quantities, of which the Mexican Indians make the heads of their arrows; and they are said, also, to make razors and knives of them. The wood is very hard, and much esteemed by the Mexicans. Q. siderózyla Humb. et Bonp. Pl. Equin., t. 85., and our fig. 1860., Michx. N. Amer. Syl., 1. p. 109. Leaves wedge-shaped, oblong; obtuse at the base; mucronate and dentate towards the tip; white with down beneath. Fruit sessile. (Humb. et Bonp.) A lofty tree, with thick rugged bark, and very hard wood. Leaves crowded, on short footstalks; 13 in. long, rigidly coriaceous; glabrous above. Female flowers generally twin, upon very short footstalks, in the axils of the leaves. Cups globose, closely imbricated. Scales membranaceous, roundish-oval, obtuse; covered externally with powdery down; scarious and naked on the margin. Nut ovate, twice as long as the cup. A native of the temperate regions of New Spain, near Villalpando, in dry and arid places, at an elevation of 8600 ft. (1440 toises). This is one of the most valuable species of oaks furnished by New Spain. It attains a great height; its wood is very compact, and capable of taking a fine polish; and it has another property, as rare as valuable, viz. that of hardening when exposed to moisture, or entirely plunged in water, and never decaying in such a situation. For this reason, it is preferred for subterraneous works, by the miners, to every other.

Q. mexicana Humb. et Bonp. Pl. Equin., t. 82., and our fig. 1861., Michx. N. Amer. Syl., 1. Leaves oblong, blunt, with a very minute point; somewhat wavy on the margin; downy beneath. Acorns slightly stipitate. A tree, from 18 ft. to 20 ft. high. Younger branches downy. Leaves about 2 in. long; white beneath with stellate down, glaucous above, shining, leathery; younger ones lanceolate, downy on both sides, quite entire. Male flowers inferior, in axillary aggregate catkins; female nearly sessile, in the axils of the leaves, almost solitary. Male flower: one concave roundish scale, instead of a calyx; stamens constantly 7, very short. Cup goblet-shaped. Scales oval, obtuse, flat, membranaceous; covered externally with a powder-like down. Nut ovate, terminated by the persistent style. Very common in Mexico. The wood is white, and neither strong nor compact; but it is much sought after for making charcoal. The young leaves have all the characters of Q. microphylla. (Nees.)

2. crássipes angustifolia Humb. et Bonp. Pl. quin., t. 84, and our fig. 1859., differs from Q. crássipes, in the leaves being narrowed, and more diminished towards the point. Found, along with Q. crassipes, near Ario, in the interior of Valladolid.

Q. crassipes Humb. et Bonp. Pl. Equin., t. 83., and our fig. 1862., Michx. N. Amer. Syl., 1.

p. 107. Leaves somewhat lanceolate-oblong; obtuse at the base, quite entire; downy beneath. Fruit on short thick stalks. (Humb. et Bonp.) A tree, from 25 ft. to 30 ft. high. Branches round, covered with minute tubercles; younger ones somewhat hairy. Leaves about 2 in. long, leathery; glabrous above; covered with pale down beneath. Petioles about 2 lines long. Female flowers in the axils of the leaves, almost solitary, on short thick pedicels. Cups somewhat top-shaped, closely imbricated. Scales oval, covered externally with a powdery down, acute. Nut ovate, terminated by the elongated style. A native of the low mountains of New Spain, near Santa Rosa. Humboldt called this species Q. crassipes, from the extreme thickness and shortness of the stalks of the acorns. Its leaves terminate in a mucro.

1863

Q. lanceolata Humb. et Bonp. Pl. quin., t. 81., and our fig. 1863., Michx. N. Amer. Syl., 1. p. 107. Leaves lanceolate, quite entire, wavy; the axils of the veins bearded beneath; shining above. Fruit sessile. Scales of the cup turned backwards. (Humb. et Bonp.) A tree, from 30 ft. to 40 ft. high. Branches alternate, covered with small tubercles, glabrous; younger ones, and the petioles, clothed with stellate down. Leaves 2 in. to 3 in. long, and 1 in. broad; shining on both sides, leathery. Petioles about in. long. Female flowers axillary, nearly sessile, and solitary. The cup is in the shape of a goblet, with the scales turned the contrary way; oval, glabrous, and convex on the outside. Nut ovate, twice the length of the cup. A native of the temperate regions of New Spain, between Moran and Santa Rosa; where it forms immense forests, at an elevation of 5400 ft. (900 toises). The wood is very hard, and will last a long time when driven into the earth, or exposed to wet; on which account it is much esteemed by the Mexicans, and is used in the works of the mines. This oak is remarkable for its leaves, which are entire and wavy on the margin; for the goblet-shaped cups of its acorns, the scales of which all point towards the tree, instead of from it; and the property which is possessed by its wood of resisting decay in water.

Q. reticulata Humb. et Bonp. Pl. quin., t. 86., and our fig. 1865., Michx. N. Amer. Syl., 1. p. 110. Leaves oboval; emarginate at the base; slightly toothed towards the tip, rugged; reticulately veined and minutely downy beneath. Fruit sessile, on a pedunculated raceme. (Humb. et Bonp.) A very lofty tree; younger branches downy. Leaves 2 in. long, a little emarginate at the base. Female flowers in axillary solitary spikes, about the length of the leaves

Cup campanulate, closely imbricate. Scales membranaceous, lanceolate, externally downy, attenuated on both margins, somewhat recurved. Nut ovate, twice as long as the cup; terminated by the persistent style. A native of arid mountains in New Spain, between Guanajuato and Santa Rosa, forming considerable forests, at an elevation of about 6700 ft. (1450 toises). It attains a great height, and the trunk is straight, and of great diameter. The wood is used in building.

Q. chrysophylla Humb. et Bonp. Pl. Æquin., t. 87., and our fig. 1864., Michx. N. Amer. Syl, 1. p. 108. Leaves oblong; obtuse at the base; S-5-pointed at the apex; yellow beneath. Female flowers in many-flowered pedunculated clusters. (Humb. et Bonp.) A tall tree; younger branches furrowed, as if with a powdery down. Leaves alternate, on long footstalks, 2 in. long, membranaceous; shining

above, covered with fine yellow tomentum beneath. Male catkins aggregate, situated beneath the female flowers. Male flower: calyx 5-toothed, stamens 6, anthers ovate, pollen yellow. Female flowers 4-6, sessile, on the apex of a peduncle about in. long. Female flower: ovary globose; styles or stigmas 5, red, thick A native of New Spain, between Moran and Pachuca. Q. chryso. phylla, as well as the preceding species, is found forming entire forests between Moran and Pa

chuca, at an elevation of 8400 ft. (1400 toises). It is remarkable, on account of the position of its female flowers, which are placed under the male flowers; and also for the beautiful golden colour of the under surface of the leaves; a peculiarity which distinguishes it from every other described species of oak. Michaux mentions that this tree is remarkable for the thinness of its foliage.

Q. pulchella Humb. et Bonp. Pl. Equin., t. 88., and our fig. 1866., Michx. N. Amer. Syl., 1. p. 110. Leaves oblong, obtuse; emarginate at the base; covered with white down beneath; teeth short, mucronate. Fruit sessile, almost solitary. (Humb. et Bonp.) A shrub from 12 ft.

to 18 ft. high, with a trunk about 2 ft. in circumference, and a smooth bark. Branches alternate, round, covered with tubercles, or callous dots. Leaves crowded towards the tips of the branches; 1 in. to 2 in. long, on longish footstalks, leathery, wavy on the margin; shining above, reticulately veined and co

the under surface with woolly tomentum. Stipules persistent. Fruit sessile, almost solitary. (Humb. et Bonp.) A tree, about 50 ft. high. Branches downy; younger ones brownish. Leaves about Sin. long; younger ones downy above; adult ones thick and rigidly coriaceous; glabrous above, covered with yellow down beneath; obtuse and somewhat emarginate at the base, acute at the apex; distinctly toothed on the upper part. Petiole in. to in. long, thick, tomentose. Stipules linear-lanceolate, persistent. Female flowers axillary, sessile, solitary or twin. Cup composed of roundish, membrana ceous, downy scales. A native of the mountains of Mexico, near Actopan; forming entire forests, at an elevation of 7900 ft. (1330 toises). It has a great affinity with Q. magnoliafolia Nee, and Q lùtea Nee (see p. 1949.); but differs in the fruit being sessile, and disposed singly or in pairs in the axils of the leaves; while, in Q. magnoliaf òlia and Q. lutea, the fruit is in racemes. It is easily known from every other species of oak by its large persistent stipules. Michaux describes it as remarkable for the thickness of its foliage.

Q. crassifolia Humb. et Bonp. Pl Equin., t. 91., and our fig. 1869., Michx. N. Amer. Syl., 1. p. 110. Leaves wedge-shaped, oboval; emarginate at the base, remotely toothed, repand; downy beneath. Peduncles short, bearing 1-3 acorns. (Humb. et Bonp.) A tree, from 40 ft. to 50 ft. high. Branches downy, angled. Leaves from 3 in. to 4 in. long, thick, and rigidly coriaceous; covered with yellow down beneath; teeth blunt, terminated by a mucro. Cups sessile on the tips of short thick peduncles. Scales roundish, downy. Nut spherical, very small, covered by the cup. A native of New Spain, near Chilpancingo. It is closely allied to Q. magnoliafolia and Q. lutea Nee;

which two kinds Humboldt considers as forming only one species. Michaux mentions that it has very thick heavy-looking foliage; and that it is found in stony and mountainous places.

Q. depressa Humb, et Bonp. Pl. Æquin., t. 92., and our fig. 1871., Michx. N. Amer. Syl., 1.

p. 108. Leaves oblong-oval, acute, entire, rarely mucronate; dentate, evergreen, quite glabrous. Fruit nearly sesssile, and solitary. (Humb. et Bonp.) An evergreen shrub, from 1ft. to 2ft. high. Branches alternate, approximate, about the thickness of a goose-quill; younger ones covered with a peculiar powdery down. Leaves 1 in.

to 1 in. long; glabrous on both sides, shining, rigid, on very short petioles. Catkins downy. Calyx small, 4-5-toothed, downy. Stamens 7-11, three times as long as the calyx, erect. Anthers ovate,